Larkspur

March 20, 2023

Life Cycle	Hardy Annual
Zone 5 Treatment	Can plant seedlings 4-6 weeks before last frost. If you get seedlings in later in the spring, they will still bloom, but likely shut down in the heat of the summer. If seeding directly, you can plant the seeds the prior fall, leave them covered all winter with a row cover and they’ll bloom in early spring.
Seedling Care	Transplant within 2 weeks of receiving otherwise the roots can get too crowded and harm the overall health of the plant.
Netting / Staking	Larkspur will need netting if you are growing in a location with high winds.
Temperature Range They Will Tolerate	28-75 degrees F
Spacing/Height	4-6” spacing36”-48”” height
Soil Preference	moisture retentive soil. Compost.
How to cut for maximum blooms	Make the first cut from the central stem, 2-3 inches above ground level. More shoots will continue to mature and develop after the central stem is harvested. Cut all future stems the same. For longest lasting flowers, cut when the first flower on the bottom of the stem opens.
Pinching	No
When to Plant if you are NOT in Zone 5	In hot summer locations, plant 4-6 weeks before first frost for blooms the same spring. Can also be planted in a cool greenhouse in winter for following spring flowers. Larkspur will re-seed itself in the garden for the following year.
Post Harvest Care	*Please remember that ALL parts of Larkspur, even the seeds are poisonous animals and can cause severe reactions if ingested in humans.Take off all of the leaves and foliage. Leaves and foliage of any cut flower should never be submerged underwater because they decay quickly in water and cause a fast build up of bacteria. Keep away from fruit & veggies.
Diseases / Insects	Because they like partial shade and moist soil, they are prone to fungal diseases and crown rot, most commonly anthracnose. Try not to overhead water if possible and use mulch to prevent mold spores from splashing from soil to the plants. Pests include aphids, Japanese beetles, and slugs are most commonResource for organically controlling aphids:https://www.arbico-organics.com/category/aphid-control-prevention-ipm Organically controlling Japanese beetles: Neem oil mix with dish soap sprayed directly on the plantOrganically controlling slugs: Sluggo applied directly into the soil.
Sweet Pea’s Notes	Larkspur are cousins of delphiniums. They have many similarities, but the main difference is that a delphinium can be a perennial and larkspur are annuals. To encourage self seeding for the following season, leave the spent flower heads on the stems even when they look dead. They produce seed at this stage and scatter naturally.
Vase Life	6-8 days